// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_PROXY_PROXY_RESOLVER_V8_H_
#define NET_PROXY_PROXY_RESOLVER_V8_H_

#include <stddef.h>

#include <memory>

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/strings/string16.h"
#include "net/base/net_export.h"

class GURL;

namespace net {
class ProxyInfo;
class ProxyResolverScriptData;

// A synchronous ProxyResolver-like that uses V8 to evaluate PAC scripts.
class NET_EXPORT_PRIVATE ProxyResolverV8 {
public:
    // Interface for the javascript bindings.
    class NET_EXPORT_PRIVATE JSBindings {
    public:
        enum ResolveDnsOperation {
            DNS_RESOLVE,
            DNS_RESOLVE_EX,
            MY_IP_ADDRESS,
            MY_IP_ADDRESS_EX,
        };

        JSBindings() { }

        // Handler for "dnsResolve()", "dnsResolveEx()", "myIpAddress()",
        // "myIpAddressEx()". Returns true on success and fills |*output| with the
        // result. If |*terminate| is set to true, then the script execution will
        // be aborted. Note that termination may not happen right away.
        virtual bool ResolveDns(const std::string& host,
            ResolveDnsOperation op,
            std::string* output,
            bool* terminate)
            = 0;

        // Handler for "alert(message)"
        virtual void Alert(const base::string16& message) = 0;

        // Handler for when an error is encountered. |line_number| may be -1
        // if a line number is not applicable to this error.
        virtual void OnError(int line_number, const base::string16& error) = 0;

    protected:
        virtual ~JSBindings() { }
    };

    // Constructs a ProxyResolverV8.
    static int Create(const scoped_refptr<ProxyResolverScriptData>& script_data,
        JSBindings* bindings,
        std::unique_ptr<ProxyResolverV8>* resolver);

    ~ProxyResolverV8();

    int GetProxyForURL(const GURL& url, ProxyInfo* results, JSBindings* bindings);

    // Get total/ued heap memory usage of all v8 instances used by the proxy
    // resolver.
    static size_t GetTotalHeapSize();
    static size_t GetUsedHeapSize();

private:
    // Context holds the Javascript state for the PAC script.
    class Context;

    explicit ProxyResolverV8(std::unique_ptr<Context> context);

    std::unique_ptr<Context> context_;

    DISALLOW_COPY_AND_ASSIGN(ProxyResolverV8);
};

} // namespace net

#endif // NET_PROXY_PROXY_RESOLVER_V8_H_
